[Mesa-stable] [PATCH] nv50/ir: use round toward 0 when converting doubles to integers

[Samuel Pitoiset]

Like floats, we should use the round toward 0 mode instead of the
nearest one (which is the default) for doubles to integers.

This fixes all arb_gpu_shader_fp64 piglits which convert doubles to
integers (16 tests).

Signed-off-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
Cc: "11.2 12.0" <mesa-stable at lists.freedesktop.org>
---
 src/gallium/drivers/nouveau/codegen/nv50_ir_from_tgsi.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/gallium/drivers/nouveau/codegen/nv50_ir_from_tgsi.cpp b/src/gallium/drivers/nouveau/codegen/nv50_ir_from_tgsi.cpp
index cd98f70..fcd4b22 100644
--- a/src/gallium/drivers/nouveau/codegen/nv50_ir_from_tgsi.cpp
+++ b/src/gallium/drivers/nouveau/codegen/nv50_ir_from_tgsi.cpp
@@ -3598,7 +3598,11 @@ Converter::handleInstruction(const struct tgsi_full_instruction *insn)
          src0 = fetchSrc(0, pos);
          src1 = fetchSrc(0, pos + 1);
          mkOp2(OP_MERGE, TYPE_U64, dreg, src0, src1);
-         mkCvt(OP_CVT, dstTy, dst0[c], srcTy, dreg);
+         Instruction *cvt = mkCvt(OP_CVT, dstTy, dst0[c], srcTy, dreg);
+         if (tgsi.getOpcode() == TGSI_OPCODE_D2I ||
+             tgsi.getOpcode() == TGSI_OPCODE_D2U) {
+            cvt->rnd = ROUND_Z;
+         }
          pos += 2;
       }
       break;
-- 
2.8.3